All Questions

Humans headed to the ISS go into quarantine for 2 weeks before launch, and if they have medical problems during that time the backup crew takes over. Was this procedure also applied when going to the ...

From what material the merlin engines and nozzles of it (sea level) are manufactured and using what processes. I am specifically interested in the alloy used to build the engine, also about the nozzle-...

During static fires of the Starship engines the exhaust goes everywhere creating a dust cloud, hitting everything with sand. Why does Spacex in Boca Chica not have a flame trench at the Starship test ...

Previously I'd mistakenly asked Would the Poynting–Robertson effect ever be faster than a solar sail from a 1 AU orbit to the Sun? when I'd meant to ask about the Yarkovsky effect which can be much ...

Crew dragon falcon 9 first stage shut down around 6700 km/hr and starlink shut down around 7900 km/hr, but around the same time. Is this because the crew dragon weighs more?

Let's assume that a spaceship (capsule) is about to dock to the ISS the distance between spaceship (capsule) and ISS is 20 meters the relative velocity between the spaceship (capsule) and ISS is ...

Soyuz is a spacecraft which still uses technologies from soviet era. The Dragon capsule is state of the art with its electronic upgrades. With Russia and US sharing the International Space Station ...

PhotoMod (1 2) is a piece of Photogrammetry software that can be used to process satellite images. I've just started using it and I would like to apply it to satellite imagery as reference to extract ...

Bennu became the smallest and probably least massive celestial body orbited by a probe. Its surface gravity is 6 micro-g (= 6 millionths the gravity of Earth) according to Wikipedia. How did a probe ...

Stage 2 landing is considerably more difficult than stage 1 landing. There is a 1:1 payload penalty in stage 2 as compared with 5:1 in stage 1. Also, stage 2 travels at 8km/sec vs 2.5km/sec in the ...

I'm trying to find equations to calculate satellite position based on orbit parameters and given time. What I currently have is a mess that is basically giving me bunch of garbage. What is latitude ...

Is the Falcon 9 second stage Merlin vacuum engine throttled down during its burn to limit the maximum acceleration experienced by the Dragon or Crew Dragon capsule? As the second stage consumes ...

We know from Hohmann-Transfer or bi elliptic transfer maneuvers that a burn in the tangential direction of an orbit changes the radius of the orbit. But what happens to an object in orbit, when there ...

After reentry, what is the speed of the Dragon 2 capsule right before splashdown? What g-force is received upon splashdown? At the time of writing, this answer gives such information for many other ...

Communication rates with probes in the outer solar systems are extremely low (Voyager is ~160 bps), because of the inverse square law and the extreme distances involved. Achieving these rates ...

I know that, Crew Dragon was initially designed for vertical landing on solid surfaces, as a reusable spacecraft, and then some changes were made to make it capable of landing in water using ...

When will the next transfer of Venus take place from the perspective of Mars? Will the next human to view one be a Martian?

I love when science fiction stories, movies, and shows are written with careful deliberation to ensure compliance with the most currently accepted laws of physics (inertia, stellar distances, etc.) ...

Could this work if the skyhook also had ion engines to maintain its orbit or would the cable just snap?

On 16 April 2018, Elon Musk posted on twitter This is gonna sound crazy, but … SpaceX will try to bring rocket upper stage back from orbital velocity using a giant party balloon And then ...

From a realistic point of view there must be a minimum speed in order to reach space in a suborbital spacecraft, let's say in a spaceplane. Like there's a first cosmic velocity (for orbit) and a 2nd ...

In terms of launch, initial orbit correction, stationkeeping, deorbiting, etc. for a typical 100-200 kg LEO satellite? Is there any source online with specifications for non-private Earth-orbiting ...

The Falcon 9's second stage is currently disposed of each flight. I know there have been some concepts by SpaceX on making it reusable, but evidently they have not yet done so. From my understanding, ...

SOOS--Stacked Oscar On Scout--was what it was called when the 1985 decision was made to replenish the Operational (Oscar) Transit constellation with unflown first-production models. Early Oscars were ...

Pictures of the octaweb show that the engines are not placed at the center of each octaweb compartment---they are closer to one side than to the other. See the picture below for an example. Focus on ...

Zuma bumped NASA for the first launch of 2018 but the mission's status remains murky. Wikipedia says: The US government has not publicly stated if there was a failure of Zuma and this secrecy has ...

I'm a CS/Engineering student at CalTech and I'm searching for a book that can help me better understand the history of spaceflight and the problems associated with getting humans to space. Since this ...

For example, Crew Dragon recently delivered two astronauts to ISS and there are at the moment 5 astronauts on board ISS. Assuming [pick your own disaster scenario] happens and all 5 astronauts had to ...

To use a touch screen wearing a pressurized suit with gloves may be not as easy as without space suit and gloves. But what about tests done under more than Earth's gravity?

I am very much aware of this question from 2018 by @uhoh - Why would InSight's arrival date at Mars be fixed, and independent of the launch date?. I was led here by a similar question which arose in ...

I know that sequential staging of rocket boosters was problematic, leading to Atlas stage-and-a-half and Russian hot staging. At what point did rocket boosters have attitude control allowing them to ...

We are creating a project in Antarctica to simulate life on Mars or the Moon. We are a global group of concerned citizens from all nations. I am new to this group so Im coming straight to the point. ...

Simple question really - would ICBMs be visible to a person from the ground on a clear night, in much the same way the Starlink satellites have been? Edit - to be clear, I'm meaning when the warheads ...

This answer explains how the liquid oxygen in a Falcon 9 is evaporation cooled to maintain a temperature well below boiling, by bubbling helium through it. The temperature difference to the ...

Since the Martian poles are water ice caps, belong to the most likely locations on Mars to host life, and the north pole being the most likely place for a crewed mission, it seems reasonable that one ...

Assuming that desired inclination is achieved during the launch, how are the target altitude and RAAN usually achieved in satellite missions, if the launch could only place the satellite on a ...

I mean launch from Earth, dock to the gateway and come back.

For the Dragon Crew mission SpaceX flew a brand new booster (how declasse) B1058 and painted it with the old style NASA Worm logo. SpaceX owns the booster and is most likely to fly it many more times ...

I've been looking at the Mars helicopter (Ingenuity) that will be onboard the Mars 2020 rover and I am having trouble figuring out how they determined the size of the rotor blades. Specifically, I'm ...

What kind/variation of Antennas are used by SpaceX and how many in Falcon 9 Rockets for the precise landing of the rocket? I don't have any kind of knowledge in antennas and communication systems ...

Many rockets designed after the V2 but prior to Saturn V, do not show the typical "Bell" shaped diverging nozzle. Why is it so? Do they achieve supersonic speeds for the exhaust gases in any other way?...

2: Is there any site which has details of "technological developments" in designs of rocket engines, recorded chronologically?

1: While German v2 might have been the base reference for future designs of rockets, many rockets do not seem to have used the "diverging" nozzle, at least their photographs do not show the "Bell" ...

Reading this question about multiple gravity assists (Why is Voyager 1 faster than all other space probes?), it caused me to wonder if any probes have been redirected to additional (or alternate) ...

The space shuttle, like most launch vehicles, was a multistage vehicle (albeit one where the various stages were mostly stuck to the sides of each other rather than being stacked vertically), reducing ...

The question is sparked in part by the "America's favorite dads in space" narrative which accompanies the recent Demo-2 mission, involving astronauts Rob Behnken and Douglas Hurley, as well as their ...

If I understand correctly, NORAD tracks thousands of satellites as well as pieces of space debris and publishes TLE files representing their orbital position and motion that are updated regularly. It ...

I want to know what is the purpose of this silvery foil situated above the bell in Merlin Vacuum Engines, and what purpose does it fulfill exactly?

After the Pioneer, Voyager and New Horizons spacecraft complete one orbit of the Milky Way (in approx. 230-250 million years or one "galactic year"), how close will they then be to our solar system? (...

@Uwe's answer to Why would sub-cooled LOX tanks need to “topped-off” until the last minute or so? explains how subcooled LOX is kept cold and dense by "in situ refrigeration"; helium is bubbled ...